Saturday, October 2, 2010

Pontiac 2.4 quad water pump replacement.

Reservoir and upper motor mount Water pump and coolant manifold.

Just completed a miserable job of replacing the water pump on a '99 Pontiac Grand Am, 2.4 quad. Things to note are thermostat is below exhaust manifold and pump also and runs off of the timing chain. Here are my step by step instructions that will make it alot easier for you to do if you ever have the oppurtunity or want to attempt to replace one?!?! Will save you $800-$1000.

1. Block car up so you can work under as well as over the passenger side fender of car, drain oil, antifreeze and remove passenger side wheel.2. On passenger side remove antifreeze reservoir and control module below that.3. Remove the 3 bolts on heat shroud of exhaust manifold.4. Disconnect exhaust from manifold- 3 nuts with 15mm deep socket. 2 of them are easily accessible from under the car with an extension. Donot let the flex end bend much or damage to its seal can occur- you do not need to twist it anyway.5. Remove nut securing the oil dipstick and coolant return hard line. The dipstick tube will come out stiff, but wiil come. Coolant return has a nut on manifold bolt and another bolt securing it to driverside of block, remove and just pull it out of the housing. there is a rubber "o" ring that will need a touch of grease to reinstall.6. Now we have complete access to remove all the bolts from the manifold and take it completely out. 2 nuts are a bugger to get at but you will figure it out. This being cleared out of the way exposes everything from the thermostat to the water pump.7. Remove 2 bolts in thermostat housing, note thermostat orientation.8. Remove the 6 bolts for the water pump backside housing. Bolts are all different sizes so lay bolts out so you will know correct placement for reinstall!!Now the fun part;9. Support engine with a jack, for removal of upper motor mount on passenger side.10. Remove the 2 nuts attaching mount to car. Completely remove the 2 large stretch bolts from the top of mount and remove mount assembly and set it aside.11. Loosen the 3 bolts on the motor block that connect it to the mount about 1/8 of an inch (a little GM trick they don't want us to know about). This will allow you to remove all timing chain cover bolts.12. Below passenger fender, remove all black plastic shrouding to expose the crank shaft pulley and remove pulley.13. Now we are ready too remove the 20+ bolts and nuts holding chain case cover on. 10mm if I remember correctly!?! Set cover aside.14. Remove outer gasket and middle gasket. They must be replaced, I paid $40 for timing chain gasket kit and that has the crank seal also that we will be replacing.15. This is the critical point. We do not want to get the chain out of time so before we loosen the chain tensioner, turn motor by hand until holes line up with holes on the back side of each cam sprocket. I use drill bits that just fit, and that will keep everything in place when we release the tension (another GM trick they don't want us to know about). Also grease pen mark cam sprocket to chain and crank sproket to chain, to again safe guard timing and eliminate a catastrophe, RIGHT!!16. Gently remove the chain guide right below the water pump sprocket.17. Remove the 2 bolts holding tensioner right below the guide that was removed. Be very gentle and all chain will stay in place.Remove the 3 bolts mounting the water pump. Gently lift chain off sprocket at the same time pulling out the water pump at slight angle. Remove the tapered water pump gasket, When you get a new water pump, I paid $48, some stores have a core charge if not, still bring old one with to verify it is correct part. (Good rule of thumb!) There should also be 3 new gaskets-tapered rubber, water pump to coolant manifold (apply high temp red silicone) and coolant manifold to block gaskets (apply high temp red silicone). VERIFY ALL PARTS BEFORE YOU LEAVE THE PARTS STORE!!

For installation follow the steps back through. Hope this helps some one out there. GOOD LUCK!